Semiconductor device having programmable interconnect layers

Abstract

An integrated circuit structure is described which includes a base semiconductor structure and a programmable semiconductor structure which are fabricated separately and later joined to form the integrated circuit structure. The base semiconductor structure includes conventional semiconductor devices fabricated in accordance with a first set of design rules. The programmable semiconductor structure includes programmable elements fabricated in accordance with a second set of design rules which may be different than the first set of design rules. The programmable elements are used to control the configuration of the integrated circuit structure or to provide field programmable devices for use in the integrated circuit structure.

We claim:  
     
       1. An integrated circuit structure comprising: 
       a base semiconductor structure, wherein active and passive regions are located in the base semiconductor structure; and  
       a programmable semiconductor structure formed separately from the base semiconductor structure and joined to the base semiconductor structure so as to form the integrated circuit structure, wherein the programmable semiconductor structure comprises at least one programmable element.  
     
     
       2. The integrated circuit structure of claim  1 , wherein the programmable element is programmable to control the configuration of the integrated circuit structure. 
     
     
       3. The integrated circuit structure of claim  1 , wherein the integrated circuit structure is a field programmable logic device and the programmable element is a field programmable element. 
     
     
       4. The integrated circuit structure of claim  1 , wherein the programmable element comprises a passive device. 
     
     
       5. The integrated circuit structure of claim  4 , wherein the passive device comprises an anti-fuse. 
     
     
       6. The integrated circuit structure of claim  4 , wherein the passive device comprises a fuse. 
     
     
       7. The integrated circuit structure of claim  4 , wherein the passive device comprises a bipolar junction. 
     
     
       8. The integrated circuit structure of claim  1 , wherein the programmable element comprises an active device. 
     
     
       9. The integrated circuit structure of claim  8 , wherein the active device comprises an EPROM cell. 
     
     
       10. The integrated circuit structure of claim  8 , wherein the active device comprises an EEPROM, a flash memory cell, an EPROM cell or a PROM cell. 
     
     
       11. The integrated circuit structure of claim  1 , further comprising: 
       a plurality of first contact elements connected to the active and passive regions of the base semiconductor structure, wherein the first contact elements are exposed at a first surface of the base semiconductor structure; and  
       a plurality of second contact elements connected to the programmable element, wherein the second contact elements are exposed at a first surface of the programmable semiconductor structure, and wherein the first contact elements are electrically connected to the second contact elements when the base semiconductor structure is joined to the programmable semiconductor structure.  
     
     
       12. The integrated circuit structure of claim  11 , wherein the first surface of the base semiconductor structure includes a bonding pad region which extends beyond the first surface of the programmable semiconductor structure when the base semiconductor structure and the programmable semiconductor structure are joined, the integrated circuit structure further comprising: 
       an insulating layer located over the first surface of the base semiconductor structure;  
       an electrically conductive element located over the insulating layer, wherein the electrically conductive element is connected to at least one of the first contact elements, the electrically conductive element extending to the bonding pad region; and  
       a bonding pad located over the insulating layer in the bonding pad region, wherein the bonding pad is connected to the electrically conductive element.  
     
     
       13. The integrated circuit structure of claim  12 , wherein the electrically conductive element is connected to at least one of the second contact elements. 
     
     
       14. The integrated circuit structure of claim  11 , wherein the first surface of the programmable semiconductor structure includes a bonding pad region which extends beyond the first surface of the base semiconductor structure when the base semiconductor structure and the programmable semiconductor structure are joined, the integrated circuit structure further comprising: 
       an insulating layer located over the first surface of the programmable semiconductor structure;  
       an electrically conductive element located over the insulating layer, wherein the electrically conductive element is connected to at least one of the second contact elements, the electrically conductive element extending to the bonding pad region; and  
       a bonding pad located over the insulating layer in the bonding pad region, wherein the bonding pad is connected to the electrically conductive element.  
     
     
       15. The integrated circuit structure of claim  14 , wherein the electrically conductive element is connected to at least one of the first contact elements. 
     
     
       16. The integrated circuit structure of claim  11 , wherein the programmable semiconductor structure has a second surface opposite the first surface of the programmable semiconductor structure, the integrated circuit structure further comprising: 
       an insulating layer located over the first surface of the programmable semiconductor structure;  
       an electrically conductive element located over the insulating layer and connected to at least one of the second contact elements;  
       an electrically conductive via plug which extends through the programmable semiconductor structure and is connected to the electrically conductive element; and  
       a bonding pad located over the second surface of the programmable semiconductor structure and connected to the via plug.  
     
     
       17. The integrated circuit structure of claim  16 , wherein the electrically conductive element is connected to at least one of the first contact elements. 
     
     
       18. The integrated circuit structure of claim  11 , wherein the base semiconductor structure has a second surface opposite the first surface of the base semiconductor structure, the integrated circuit structure further comprising: 
       an insulating layer located over the first surface of the base semiconductor structure;  
       an electrically conductive element located over the insulating layer and connected to at least one of the first contact elements;  
       an electrically conductive via plug which extends through the base semiconductor structure and is connected to the electrically conductive element; and  
       a bonding pad located over the second surface of the base semiconductor structure and connected to the via plug.  
     
     
       19. The integrated circuit structure of claim  18 , wherein the electrically conductive element is connected to at least one of the second contact elements.